well your BR is rather high at that point in the game as i was only BR34 fighting him got creamed the first time but used a different formation (Pincers' Grip Formation) the second time and destroyed him and im just after getting past him a couple of hours ago.........
you see the higher the BR is the higher the enemy HP is and they can use stronger forms of there attacks........
also this is great for anything you need on this game:
http://lastremnant.wikia.com/wiki/The_Last_Remnant_Storyline